If you want to live forever, one of the main things stopping you is cancer. Many of the mechanisms that prevent cells from aging also make those cells prone to carcinogenic mutations. But now a research team at the University of Rochester has discovered that small rodents like chinchillas (pictured) manage to live decades without developing cancer. In a paper published today in Aging Cell, biologist Vera Gorbunova explains how the furry, dusty chinchilla may become the unlikely key to humans living for centuries. Apparently the chinchilla and other small rodents of its type have cells that are better than humans' at sensing when cancer is developing. As soon as cancerous growths are detected, the rodent's body slows down cell division, halting the expansion of the tumor and preventing metastasis. Gorbunova and colleagues suspect that the human body could be induced to do the same thing, essentially curing its own cancer by becoming very efficient at self-monitoring. One of the interesting outcomes of this study had to do with the rodents' levels of telomerase, an enzyme that regulates cell aging and also causes cancer. According to the University of Rochester:

Gorbunova and colleagues showed that it was not life expectancy, but body mass that regulated the expression of telomerase. Simply having more cells increases the likelihood that one will become cancerous. We humans, as large animals, would likely develop cancer much more often and much earlier if we didn't suppress our telomerase.

So the bigger you are, the more likely you'll start mutating. Said Gorbunova:

We haven't come across this anticancer mechanism before because it doesn't exist in the two species most often used for cancer research: mice and humans. Mice are short-lived and humans are large-bodied. But this mechanism appears to exist only in small, long-lived animals.